class Solution24 {
    public boolean[][] row;//行
    public boolean[][] col;//列
    public boolean[][][] grid;//小方格
    public boolean isValidSudoku(char[][] board) {
        row = new boolean[9][10];
        col = new boolean[9][10];
        grid = new boolean[3][3][10];
        for(int i = 0; i < 9; i++) {
            for(int j = 0; j < 9; j++) {
                if(board[i][j] != '.') {
                    int num = board[i][j] - '0';
                    if(row[i][num] == true || col[j][num] == true || grid[i/3][j/3][num] == true) return false;
                    else row[i][num] = col[j][num] = grid[i/3][j/3][num] = true;
                }
            }
        }
        return true;
    }
}